Clarify we only use vote only hash in fork selection.

proposals/0165-async-vote-execution.md

@@ -191,7 +191,10 @@ everyone receives the same block.
 transactions without checking the fee payers. The result is immediately
 applied in consensus to select a fork. Then votes are sent out for the
 selected fork with the `Vote only bankhash` for the tip of the fork and the
-most recent `Replay tip bankhash`.
+most recent `Replay tip bankhash`. Note that the fork selection will only
+be picked based on most recent `Vote only bankhash` and associated slot.
+`Replay tip bankhash` is used mostly for commitmment aggregation and security
+checks described below.
 3. The blocks on the selected forks are scheduled to be replayed. When
 a block is replayed, all transactions are executed with fee payers checked.
 This is the same as the replay we use today.